Hippeastrum (Amaryllidaceae family) is a bulbous plant with strap-like foliage. Commonly called amaryllis, it is no longer considered to belong to that genus of South African flowering bulbs but is instead part of the new world genus Hippeastrum. It is prized for its beautiful trumpet shaped flowers that come in a wide variety of colors. Flowers can be almost all one color; others have margins, streaking, or throat markings of various color or shades. They are very striking decorative flowering plants to enjoy.
This South American native is easy to care for and can be forced into bloom again and again. It has a dormant rest period when leaves dry up. The bulbs are usually widely available as breeders have concentrated on developing many hybrids.
Amaryllis needs bright light, with some direct sunlight during the active growth period, and no light required when in dormancy. Continue giving bright light from the time flowers fade until mid-fall to contribute to subsequent flowering.
Newly planted bulbs are best watered sparingly, just enough to keep potting soil barely moist, until the roots develop (indicated by the appearance of new healthy growth). Thereafter, water moderately, by letting the top half of the soil mixture dry out between waterings. When the plant is in full growth keep the soil mixture moist just below the bulb. When active growth period has ended, you can continue to water at a reduced scale for quite a while, but it is best to stop in mid-fall, so the bulb begins to get into an enforced rest period.
When watering stops, the foliage will yellow and wither away naturally and can be removed. If watering is continued too long, the past year's foliage will remain green and may become unattractive and unwieldy. Keep the potting mixture completely dry throughout the needed rest period, which lasts until new growth starts to appear (usually flower tip starts to show).
Normal room temperature will encourage good growth and early flowering, but too much heat will considerably shorten flowering life. A temperature no higher than about 55-70 degrees F. is best during early growth and flowering period. A temperature of around 50 degrees F. is best for fall dormancy.
Provide a liquid fertilizer once every two weeks from the time flowers have finished blooming until midsummer. Then you can switch to a high-potash fertilizer to ensure a flowering stalk the following year. Stop feedings after mid-fall.
If you receive a bare root Hippeastrum bulb, set singly in a 5- to 7-inch pot; half-bury the bulb, leaving its neck and shoulders clear of the potting mixture. Some growers believe soaking the bases of new dry bulbs for 24 hours in shallow saucers of water can help initial growth. You can also place the newly potted bulb on a plant heating mat set to 70 degrees to stimulate growth. Most bulbs take 2 to 8 weeks to initiate growth.
In subsequent years, after dormancy period, when the bulb begins to grow, remove the top 1/2" of the soil to replace with fresh potting soil mixture. Do not remove the bulb from the pot and water soil thoroughly and place plant back in its bright light area. New bulbs should be
Amaryllis dislikes root disturbance but can be repotted every 3-4 years after the initial potting up. After dormancy, and after 3-4 years, when the bulb begins to show new signs of growth, repot to the next larger size container after removing (shaking off) the old potting soil mixture from the roots carefully and then add fresh potting soil into pot add bulb and add soil halfway up the bulb and an inch below the pot's top. Use a potting soil mixture of equal parts sterilized houseplant potting soil high in organic matter, peat moss and sand/or perlite (added broken clay shards to pots' bottom is optional to help drainage). Place your newly potted bulb in good light and water when needed thoroughly then toss excess water from catch saucer.
Detach the small bulblets with roots, which can grow around the base of the parent bulb when they are about 1" to 1½" across. Be sure to keep the good root system with each offset bulb. Plant each young bulbs in small containers (3-inch pot) at the same time the parent bulb is transplanted. Treat young bulb plants like mature ones but move them into slightly larger pots yearly until they have grown to flowering size (3 - 3 1/2 inches across).
Once your amaryllis flowers have died down, you can remove them by cutting the flowering stalk all the way down. Place the plant in full window light, continuing watering (on a reduced scale) for a while. It is best to stop watering completely in mid-fall, so that the bulb begins its enforced rest period. If watering is continued too long, the past year's foliage will remain green and may become unwieldy and unattractive. The plant won't receive the rest it needs to bloom again. For flowers in December, initiate dormancy in earliest September. Dutch bulbs will probably not flower until late winter. Most large modern Hippeastrum bulbs don't require a dormancy period, but inducing dormancy allows you to control when you want the plant to bloom.
Store the potted bulb in a dry cool place at 50 degrees F. When the bulb begins to show signs of growth after the dormancy period, top-dress by removing 1/2" of topsoil from the pot, and replace with fresh potting mix. Water the potted bulb once thoroughly and place in bright window light.
If possible, bring your potted bulbs outdoors for the spring or summer after all danger of frost is past. Keep them in areas of morning sun or light shade to prevent burning of foliage. Before bringing indoors clean up pot and check soil and plant for any insects.
In winter, be sure to keep the foliage away from a cold windowpane as leaves can freeze and protect from too hot an area due to a heat source.
If a Hippeastrum produces lots of leaves at the beginning of the growing season, it is unlikely that the bulb will produce a flowering stem. The first thing to emerge from the bulb is usually a new stem with a flowering bud growth, a good sign that it will bloom on the tall stem.
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